"Technically speaking, it's more like fascism," Mackey said of the Affordable Care Act. "Socialism is where the government owns the means of production. In fascism, the government doesn't own the means of production, but they do control it, and that's what's happening with our healthcare programs and these reforms."

The term "fascism" was first used to describe the right-wing regime of Italian leader Benito Mussolini, and was later applied to the Nazis and the authoritarian leadership of Francisco Franco in Spain.

Mackey made headlines in 2009 for a Wall Street Journalop-ed that compared healthcare reform to socialism.

He co-founded Whole Foods, the popular chain of natural-foods supermarkets, in 1980.